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diff --git a/doc/collink.html b/doc/collink.html new file mode 100644 index 0000000..0b94bc7 --- /dev/null +++ b/doc/collink.html @@ -0,0 +1,1059 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<html> + <head> + <title>collink</title> + <meta http-equiv="content-type" content="text/html; + charset=ISO-8859-1"> + <meta name="author" content="Graeme Gill"> + </head> + <body> + <h2><b>link/collink</b></h2> + <h3>Summary</h3> + Link two ICC device profiles to create an ICC device link profile.<br> + <br> + <b> collink</b> takes two device ICC profiles, and links them + together, either in a simple fashion using the standard ICC forward + and reverse tables of the specified intent, or using color + appearance space and true gamut mapping, together with possibly + inverting the forward profile, to allow black ink regeneration + or to retain the source black characteristic from the source + profile.<br> + <h3>Usage Summary</h3> + <small><span style="font-family: monospace;">collink [-options] <span + style="font-style: italic;">srcprofile dstprofile + linkedprofile</span></span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#v">-v</a><span + style="font-family: monospace;"> + + + Verbose<br> + </span></small><small><span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#A">-A "manufacturer"</a><span + style="font-family: monospace;"> Set the manufacturer + description string</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#M">-M "model"</a><span + style="font-family: monospace;"> + Set the model + description string</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#D">-D "description"</a><span + style="font-family: monospace;"> Set the profile + Description string (Default "</span><span + style="font-style: italic; font-family: monospace;">inoutfile</span><span + style="font-family: monospace;">")</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#C">-C "copyright"</a><span + style="font-family: monospace;"> Set the + copyright string</span></small><br style="font-family: + monospace;"> + <small><span style="font-family: monospace;"></span><span + style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#V">-V</a><span + style="font-family: monospace;"> +Verify +existing + + + profile, rather than link (Debug option)</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#q">-q lmhu</a><span + style="font-family: monospace;"> + Quality - Low, Medium (def), + High, Ultra</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#r">-r <i>res</i></a><span + style="font-family: monospace;"> +Override +clut + + + res. set by -q</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#n">-n</a><span + style="font-family: monospace;"> +Don't +preserve + + + device curves in result</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#f">-f</a><span + style="font-family: monospace;"> + + Special :- Force neutral colors + to be K only output.<br> + </span></small><small><span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#fk">-fk</a><span + style="font-family: monospace;"> + + Special :- Force K only neutral colors + to be K only output<br> + </span></small><small><span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#fcmy">-fcmy</a><span + style="font-family: monospace;"> + + Special :- Force 100% C,M or Y only to stay pure</span></small><br + style="font-family: monospace;"> + <small><span style="font-family: monospace;"></span><span + style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#F">-F</a><span + style="font-family: monospace;"> + + Special :- Force all colors to be + K only output.</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#p">-p aprof.icm</a><span + style="font-family: monospace;"> +Include + + + abstract profile in link</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#s">-s</a><span + style="font-family: monospace;"> +Simple +Mode + + + (default)</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#g">-g [src.gam]</a><span + style="font-family: monospace;"> + Gamut Mapping Mode [optional source image gamut]</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#G">-G [src.gam]</a><span + style="font-family: monospace;"> +Gamut + + + Mapping Mode using inverse outprofile A2B [optional source + gamut]</span><br style="font-family: monospace;"> + <br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><u + style="font-family: monospace;">Simple Mode Options:</u><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#si">-i <i>in_intent</i></a><span + style="font-family: monospace;"> p = + perceptual, r = relative colorimetric,</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> + +s + + + = saturation, a = absolute colorimetric</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#so">-o </a><i + style="font-family: monospace;"><a href="#so">out_intent</a> </i><span + style="font-family: monospace;"> p = + perceptual, r = relative colorimetric,</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> + +s + + + = saturation, a = absolute colorimetric</span><br + style="font-family: monospace;"> + <br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><u + style="font-family: monospace;">Mapping Mode Options:</u><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#i">-i <i>intent</i></a><span + style="font-family: monospace;"> + set linking intent from the following choice:</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> +a +- + + + Absolute Colorimetric (in Jab) [ICC Absolute Colorimetric]<br> + +aw +- + + + Absolute Colorimetric (in Jab) with scaling to fit white point<br + style="font-family: monospace;"> + </span><span style="font-family: monospace;"> +aa +- + + + Absolute Appearance</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> +r +- + + + White Point Matched Appearance [ICC Relative Colorimetric]</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> +la +- + + + Luminance matched Appearance</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> +p +- + + + Perceptual (Preferred) [ICC Perceptual]<br> + </span></small><small><span style="font-family: monospace;"> +pa + + + - Perceptual Appearance</span></small><br style="font-family: + monospace;"> + <small><span style="font-family: monospace;"></span><span + style="font-family: monospace;"> +ms +- + + + Saturation</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> +s +- + + + Enhanced Saturation [ICC Saturation]</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> +al +- + + + Absolute Colorimetric (Lab)</span><span style="font-family: + monospace;"></span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#w">-w [J,a,b]</a><span + style="font-family: monospace;"> Use forced + whitepoint hack [optional color to map the white to]</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#c">-c <i>viewcond</i></a><span + style="font-family: monospace;"> set source viewing + conditions for CIECAM02,</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> + +either + + + an enumerated choice, or a parameter</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#d">-d <i>viewcond</i></a><span + style="font-family: monospace;"> set destination + viewing conditions for CIECAM02,</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> + +either + + + an enumerated choice, or a parameter:value change<br> + </span></small><small><span style="font-family: monospace;"> + pp - Practical + Reflection Print (ISO-3664 P2)</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> + + + + + pe - Print evaluation environment (CIE 116-1995)<br> + </span></small><small><span style="font-family: monospace;"> + + + + + pc - Critical print evaluation environment (ISO-3664 P1)</span></small><small><span + style="font-family: monospace;"></span><span style="font-family: + monospace;"></span><span style="font-family: monospace;"></span><span + style="font-family: monospace;"></span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> + mt - Monitor in + typical work environment</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> + + + + + mb - Monitor in bright work environment</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> + md - Monitor in darkened work + environment</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> + jm - Projector in dim + environment</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> + jd - Projector in dark + environment</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> + pcd - Photo CD - original scene + outdoors</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> + ob - Original scene - Bright + Outdoors</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> + cx - Cut Sheet Transparencies + on a viewing box</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> +s:surround +n + + + = auto, a = average, m = dim, d = dark,</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> + + + + + c = transparency (default average)</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> +w:X:Y:Z +Adapted + + + white point as XYZ (default media white)</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> +w:x:y +Adapted + + + white point as x, y</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> +a:adaptation +Adaptatation + + + luminance in cd.m^2 (default 50.0)</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> +b:background +Background +% + + + of image luminance (default 20)<br> + l:scenewhite + Scene white in cd.m^2 if surround = auto (default 250)<br + style="font-family: monospace;"> + </span><span style="font-family: monospace;"> +f:flare +Flare +light + + + % of image luminance (default 1)</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> +f:X:Y:Z +Flare + + + color as XYZ (default media white)</span><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> +f:x:y +Flare + + + color as x, y</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#t">-t <i>tlimit</i></a><span + style="font-family: monospace;"> +set +source + + + total ink limit, 0 - 400% (estimate by default)</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#T">-T <i>klimit</i></a><span + style="font-family: monospace;"> +set +source + + + total ink limit, 0 - 100% (estimate by default)</span><br + style="font-family: monospace;"> + <br style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><u + style="font-family: monospace;">Inverse outprofile A2B Options:</u><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#k">-k tezhxr</a><span + style="font-family: monospace;"> + CMYK Black generation</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> + +t + + + = transfer K from source to destination, e = retain K of + destination B2A table</span><br style="font-family: monospace;"> + <span style="font-family: monospace;"> + +z + + + = zero K, h = 0.5 K, x = maximum K, r = ramp K (default)</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#kp">-k p stle stpo enpo + enle shape</a><br style="font-family: monospace;"> + <span style="font-family: monospace;"> + +p + + + = black level generation curve parameters</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#kq">-k q stle0 stpo0 + enpo0 enle0 shape0 stle2 stpo2 enpo2 enle2 shape2</a><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> + +q + + + = transfer source K to dual curve limits</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#K">-K parameters</a><span + style="font-family: monospace;"> + Same as -k, but target is K locus rather than K value itself</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#l">-l <i>tlimit</i></a><span + style="font-family: monospace;"> +set +destination + + + total ink limit, 0 - 400% (estimate by default)</span><br + style="font-family: monospace;"> + <span style="font-family: monospace;"> </span><a + style="font-family: monospace;" href="#L">-L <i>klimit</i></a><span + style="font-family: monospace;"> +set +destination + + + total ink limit, 0 - 100% (estimate by default)<br> + </span></small> <small><span style="font-family: + monospace;"><a href="#P">-P</a> + +Create +gamut + + + gammap_p.wrl and gammap_s.wrl diagostics</span></small><small><br> + <br> + <span style="font-family: monospace;"></span></small><span + style="font-family: monospace;"> <span + style="text-decoration: underline;"><span style="font-style: + italic;"></span></span></span><a href="#p1"><i + style="font-family: monospace;">srcprofile</i></a><span + style="font-family: monospace;"> +source +ICC + + + profile. A </span><small><span style="font-family: monospace;">TIFF + + + or JPEG file with embedded profile may be used here.</span></small><br + style="font-family: monospace;"> + <span style="font-family: monospace;"><span + style="text-decoration: underline;"><span style="font-style: + italic;"></span></span></span><a href="#p2"><i + style="font-family: monospace;">dstprofile</i></a><span + style="font-family: monospace;"> +destination +ICC + + + profile. </span><span style="font-family: monospace;">A </span><small><span + style="font-family: monospace;">TIFF or JPEG file with embedded + profile may be used here.</span></small><br style="font-family: + monospace;"> + <span style="font-family: monospace;"> </span><a href="#p3"><i + style="font-family: monospace;">linkedprofile</i></a><span + style="font-family: monospace;"> + resulting device link profile</span><br> + <h3>Usage Details and Discussion</h3> + <b><a name="v"></a> -v</b> Turns on verbose mode. Gives progress + information as the profile is created. Since gamut map mode inverse + profile linking can take a long time to perform, this is often + useful. <br> + <br> + <a name="A"></a>The <b>-A</b> parameter allows setting of the + device manufacturer description tag. This parameter may not be + relevant for a link profile, but if used should be a string that + identifies the manufacturer of the primary device used in the link. + With most command line shells, it will be necessary to enclose the + parameter with double quotes, so that spaces and other special + characters are included in the parameter, and not mistaken for the + start of another flag, or as a final command line parameters. By + default no manufacturer description string tag will be generated for + the profile.<br> + <br> + <a name="M"></a>The <b>-M</b> parameter allows setting of the + device mode description tag. This parameter may not be relevant for + a link profile, but if used should be a string that identifies the + particular model of primary device used in the link. With most + command line shells, it will be necessary to enclose the parameter + with double quotes, so that spaces and other special characters are + included in the parameter, and not mistaken for the start of another + flag, or as a final command line parameters. By default no model + description string tag will be generated for the profile.<br> + <br> + <a name="D"></a>The <b>-D</b> parameter allows setting of the + profile description tag. The parameter should be a string that + describes the profile. On many systems, it will be this string that + will be used to identify the profile from a list of possible + profiles. With most command line shells, it will be necessary to + enclose the parameter with double quotes, so that spaces and other + special characters are included in the parameter, and not mistaken + for the start of another flag, or as a final command line parameter. + Many programs that deal with ICC profiles use the description tag to + identify a profile, rather than the profile filename, so using a + descriptive string is important in being able to find a profile. By + default, the base name of the resulting profile will be used as the + description.<br> + <br> + <a name="C"></a>The <b>-C</b> parameter allows setting of the + profile copyright tag. The parameter should be a string that + describes the copyright (if any) claimed on the profile being + generated.. With most command line shells, it will be necessary to + enclose the parameter with double quotes, so that spaces and other + special characters are included in the parameter, and not mistaken + for the start of another flag, or as a final command line + parameters. By default a generic copyright string will be generated + for the profile.<br> + <br> + <br> + <b><a name="V"></a> -V</b> Verifies an existing profile. This is + really a debugging option. It is only useful if all the linking + parameters are identical to those used during the creation of the + profile being verified.<br> + <br> + <b><a name="q"></a> -q [lmhu]</b> Quality + - Low, Medium (def), High, Ultra<br> + <b><a name="r"></a> -r res </b> + + + + + Override clut res. set by <b>-q</b><br> + <br> + This sets the basic quality of the resulting link, by choosing the + resolution of various tables in the resulting profile, as well as + the resolution of other temporary tables used in creating the link. + The <b>-r</b> flag allows overriding the resolution set by the <b>-q</b> + option, for the ICC profile CLUT multi-dimensional interpolation + table. It is highly recommended that <span style="font-weight: + bold;">-qm</span> be used as a starting point, and other settings + only tried after this has been evaluated. <span style="font-weight: + bold;">-qu</span> should almost never be used, except to prove + that it should almost never be used.<br> + <br> + <a name="n"></a>Normally the per channel device curves in the source + and destination profiles are preserved in the resulting device link + profile, but the <b>-n</b> option disables this. This can be useful + if the device linearisation curves are inappropriate in nature.<br> + <br> + <a name="f"></a> The <b>-f</b> option is a special purpose flag + useful only for 3 or 4 component (RGB, CMY or CMYK) source to CMYK + destination linking, that causes the destination to be <span + style="font-weight: bold;">K only</span> for neutral axis input. + Neutral axis input is assumed for R=G=B or C=M=Y input values. So as + to get a smooth mapping from the source to the K only destination, + by default the gamut mapping will be adjusted to target the + destination K only black, and Perceptual gamut mapping will be + selected along with maximum K inking. If other options are selected + that conflict with achieving a smooth mapping, warnings messages + will be emitted.<br> + <br> + <a name="F"></a> The <b>-F</b> option is a special purpose flag + useful only mapping to a CMYK destination, that causes the + destination to be converted to K only monochrome. So as to get a + smooth mapping from the source to the K only destination, by default + the gamut mapping will be adjusted to target the destination K only + black, and Perceptual gamut mapping will be selected along with + maximum K inking. If other options are selected that conflict with + achieving a smooth mapping, warnings messages will be emitted.<br> + <br> + <a name="fk"></a> The <b>-fk</b> option is a special purpose + flag useful only for CMYK source to CMYK destination linking, that + causes K only source values to map to K only destination values. + This is often useful in re-targeting CMYK material while preserving + K only text and graphics. So as to get a smooth mapping from the + source to the K only destination, by default the gamut mapping will + be adjusted to assume K only black source to destination K only + black for K only values, and Perceptual gamut mapping will be + selected along with a black generation rule (<span + style="font-weight: bold;">-kt</span>) that preserves the black + level from source to destination. If other options are selected that + conflict with achieving a smooth mapping, warnings messages will be + emitted.<br> + <br> + <a name="fcmy"></a> The <b>-fcmy</b> options are special + purpose flags useful only for CMY or CMYK source to CMY or CMYK + destination linking. The <span style="font-weight: bold;">cmy</span> + flags may be used independently or in combination (ie. <span + style="font-weight: bold;">-fc, -fm, -fy, -fcm, -fcy, -fmy, -fcmy</span>) + or combined with the <span style="font-weight: bold;">-fk</span> + option. These flags ensure that the pure 100% primary colorant + source values map to 100% pure colorant destination values, and may + be useful in some situations where CMYK material is being + re-targeted. <span style="font-weight: bold;">Note</span> that + forcing the 100% colorant values to map this way largely works + against the aims of color management in preserving colors + appearance. So as to get a smooth mapping from the source + to destination, by default the gamut mapping will a Saturation + intent with 100 percept alignment of the selected C, M and/or Y cusp + values. A Saturation intent is often what is desired in such CMYK to + CMYK re-renderings, as it makes best use of the (usually quite + similar sized) destination gamut. If other options are selected that + conflict with achieving a smooth mapping, warnings messages will be + emitted.<br> + <br> + <a name="p"></a> The <b>-p</b> option alows specifying an abstract + profile be applied between the source and destination profiles. An + abstract profile is a way of specifying a color adjustment in a + device independent way. The abstract profile might have been created + using one of the <span style="font-weight: bold;">tweak</span> + tools, such as <a href="refine.html">refine</a>.<br> + <br> + The basic linking style is chosen by using the <b>-s</b> (default), + <b>-g</b> or <b>-G</b> flags. The three behaviors are:<br> + <br> + <a name="s"></a> <b>-s</b> Simple mode. No gamut + mapping is performed, the selected intent AtoB and BtoA tables are + simply concatenated to create the output link, with the gamut + mapping behavior being determined solely by the BtoA table. The -i + and -o options allow selection of the source and destination ICC + intents. This is typically how other CMS do ICC linking. <a + href="#ss">Details</a>.<br> + <br> + <a name="g"></a> <b>-g</b> Gamut mapping mode. In + this mode, the absolute colorimetric AtoB and BtoA tables are used + to perform the link, and the intermediate linking color space is + (generally) the CIECAM02 Jab appearance space. The source and + destination viewing conditions can be selected using the <b>-c</b> + and <b>-d</b> options. A gamut mapping is performed between the two + spaces, using the intent selected by the <b>-i</b> option. + There is an optional argument, which is a source gamut to use + instead of that of the source profile. This is to allow optimizing + the gamut mapping to a source gamut of a particular image, + which can give slightly better results that gamut mapping from the + gamut of the source colorspace. Such a source image gamut can be + created using the <a href="tiffgamut.html"> tiffgamut</a> tool. + More <a href="#gg">details</a> about gamut mapping mode.<br> + <br> + <a name="G"></a> <b>-G</b> Use the gamut mapped, inverse + AtoB table linking method. This is generally the most accurate, + smooth and flexible linking method, but takes the longest to + perform. The gamut mapping mode (<span style="font-weight: + bold;">-g</span>) options <b>-i</b>, <b>-c</b>, <b>-d</b>, <b>-k</b> + and <b>-l</b> are effective when this method is selected. There is + an optional argument, which is a source gamut to use instead of that + of the source profile. This is to allow optimizing the gamut mapping + to a source gamut of a particular image, which can give + slightly better results that gamut mapping from the gamut of the + source colorspace. Such a source image gamut can be created using + the <a href="tiffgamut.html"> tiffgamut</a> tool. More <a + href="#GG">details</a> about the gamut mapping, inverse AtoB mode.<br> + <br> + The gamut provided to the <span style="font-weight: bold;">-g</span> + or <span style="font-weight: bold;">-G</span> flag should be in the + same colorspace that <span style="font-weight: bold;">collink</span> + is using internally to connect the two profiles. For all intents + except the last one (no. <span style="font-weight: bold;">7</span>), + + + the space should be Jab appearance space, with the viewing + conditions generally being those of the source profile viewing + conditions. The source profile will normally be the one used to + create a source image gamut using <span style="font-weight: bold;">tiffgamut</span>.<br> + <br> + <u><a name="ss"></a> Simple mode gamut mapping options:</u><br> + <br> + <a name="si"></a> <b>-i</b> <i>in_intent</i> + + + + + <b>p</b> = perceptual, <b>r</b> = relative colorimetric,<br> + + <b>s</b> + = saturation, <b>a</b> = absolute colorimetric<br> + <a name="so"></a> <b>-o</b> <i>out_intent</i> + <b>p</b> = perceptual, <b>r</b> = relative + colorimetric,<br> + + <b>s</b> + = saturation, <b>a</b> = absolute colorimetric<br> + <br> + These two options simply select the appropriate ICC table, according + to desired intent. Generally, it is a good idea to use the same + intent for both source and destination. Not all ICC profiles support + all four intents.<br> + <br> + <u><a name="gg"></a> Gamut mapping mode options:</u><br> + <br> + <a name="i"></a> <b>-i</b> <i>intent</i><br> + <br> + Select the gamut mapping intent. In gamut mapping mode there is only + a single overall intent. The intent is selected using the 1 two + letter option parameter, the standard ICC profile being a subset of + the available selections.<br> + <br> + <div style="margin-left: 40px;"><a name="ia"></a>The <span + style="font-weight: bold;">a</span> intent, Absolute + Colorimetric, is intended to reproduce colors exactly, + irrespective of the white point of the each medium. This is done + using CIECAM02 Jab appearance colorspace by forcing the source and + destination to have a common white point (but other aspects of the + individual viewing conditions are active), and colors are mapped + directly from source to destination, clipping any out of gamut + colors to the closest match. This is equivalent to the ICC <span + style="font-weight: bold;">Absolute Colorimetric</span> intent, + and is often used for proofing purposes. <br> + <br> + <a name="iaw"></a>The <span style="font-weight: bold;">aw</span> + intent, Absolute Colorimetric with scaling to fit white point, is + very similar to the <span style="font-weight: bold;">a</span> + intent, except that it will scale the source colorspace down in + order to make sure that the source white point isn't clipped by + the gamut of the destination. This might be used in some print + proofing situations where the source white is lightly lighter than + the destination white (as an alternative to using the <a + href="#w">-w</a> flag), or it may be useful in some soft + proofing situations where the differences in white point of the + display destination would cause clipping of the source white + point. When the <a href="#v">-v</a> flag is on, the scaling + factor used will be displayed during execution.<br> + <br> + <a name="iaa"></a>The <span style="font-weight: bold;">aa</span> + intent, Absolute Appearance, simply maps the Jab colors directly + from source to destination, clipping any out of gamut colors to + the closest match. This attempts to match the exact appearance of + colors as closely as possible, but may not exactly map the white + point of the source to the destination, depending on how different + the viewing conditions are.<br> + <br> + <a name="ir"></a>The <span style="font-weight: bold;">r</span> + intent is like Absolute Appearance mode, but maps the white point + from source to destination precisely, and otherwise maps the Jab + colors directly from source to destination, clipping any out of + gamut colors to the closest match. This is equivalent to the ICC <span + style="font-weight: bold;">Relative Colorimetric</span> intent.<br> + <br> + <a name="ila"></a>The <span style="font-weight: bold;">la</span> + intent, Luminance matched appearance, linearly compresses or + expands the the luminance axis to match the source to the + destination space, while not otherwise altering the gamut, + clipping any out of gamut colors to the closest match. This is + often useful for appearance based soft proofing.<br> + <br> + <a name="ip"></a>The <span style="font-weight: bold;">p</span> + intent, Perceptual, uses "knee" type 3 Dimensional compression to + make the source gamut fit within the destination gamut. As much as + possible, clipping is avoided, hues and the overall appearance is + maintained. The white point is mapped precisely from source to + destination.This is equivalent to the ICC <span + style="font-weight: bold;">Perceptual</span> intent.<br> + <br> + <a name="ipa"></a>The <span style="font-weight: bold;">pa</span> + intent, Perceptual Appearance uses "knee" type 3 Dimensional + compression to make the source gamut fit within the destination + gamut. As much as possible, clipping is avoided, hues and the + overall appearance is maintained. The white point is<span + style="font-weight: bold;"> not</span> mapped from source to + destination, allowing the apperance parameters to alter the + chromatic mapping.<br> + <br> + <a name="ims"></a>The <span style="font-weight: bold;">ms</span> + intent, Saturation, uses 3 Dimensional compression and <span + style="text-decoration: underline;">expansion</span> to try and + make the source gamut exactly match the destination gamut, and + also favours higher saturation over hue or lightness preservation. + The white point is mapped precisely from source to destination.<br> + <br> + <a name="is"></a>The <span style="font-weight: bold;"></span><span + style="font-weight: bold;">s</span> intent, Enhanced Saturation, + uses the same basic gamut mapping as <span style="font-weight: + bold;">ms</span>, Saturation, but increases saturation slightly + in highly saturated areas of the gamut. This is equivalent to the + ICC <span style="font-weight: bold;">Saturation</span> intent. + The white point is mapped precisely from source to destination.<br> + <br> + <a name="ial"></a>The <span style="font-weight: bold;">al</span> + intent, Absolute Appearance (Lab), is similar to intent <span + style="font-weight: bold;">a</span>, but L*a*b* colorspace is + used rather than CIECAM02 Jab appearance space. This often leads + to poor reproduction of blue and red hues, but can be useful as a + reference mapping.<br> + </div> + <br> + <a name="w"></a> The <b>-w</b> flag forces the white points to be + mapped from source to destination, irrespective of the intent + chosen. This is useful if absolute intent is being used, and the two + media white points should match, but don't quite due to measurement + error.<br> + The <b>-w</b> flag can optionally be followed by three numbers, + that specify a color that white should be mapped to. This will be in + the colorspace used during linking (typically Jab space, which has + similar characteristics to L*a*b* space). This options can be useful + in fine tuning paper emulation in absolute colorimetric mapping + mode.<br> + <br> + <a name="c"></a><a name="d"></a> The <b>-c</b> and <b>-d</b> + options allow specification of the viewing conditions for the source + and destination colorspaces respectively. The viewing condition + information is used to map the profile PCS (Profile Connection + Space, which us either XYZ or L*a*b*) color into appearance space + (CIECAM02), which is a better colorspace to do gamut mapping in. The + viewing conditions allow the conversion into appearance space to + take account of how color will be seen under particular viewing + conditions.<br> + Viewing conditions can be specified in two basic ways. One is to + select from the list of "pre canned", enumerated viewing conditions, + choosing one that is closest to the conditions that are appropriate + for the media type and situation. Alternatively, the viewing + conditions parameters can be specified in detail individually. If + both methods are used, them the chosen enumerated condition will be + used as a base, and its parameters will then be individually + overridden.<br> + <br> + <a name="t"></a> The <b>-t</b> <i>tlimit</i> parameter sets the + total ink limit (TAC, Total Area Coverage) for a CMYK source + profile, as a total percentage from 0% to 400%. This affects the + gamut assumed for the source profile. By default, a total ink limit + will be estimated from the source profile B2A table.<br> + <br> + <a name="T"></a> The <b>-T</b> <i>klimit</i> parameter sets the + black channel ink limit for a CMYK source profile, as a total + percentage from 0% to 100%. This affects the gamut assumed for the + source profile. By default, a black ink limit will be estimated from + the source profile B2A table.<br> + <br> + <br> + <u> <a name="GG"></a>Inverse outprofile A2B Options:</u><br> + <br> + When the <b>-G</b> flag is used, the A2B table is inverted "on the + fly", allowing various additional choices as to what device values + are used to reproduce a particular color. (If the <b>-G</b> flag is + not used, then such decisions are encoded in the B2A table in the + profile, and cannot be altered during linking).<br> + <br> + <a name="k"></a> -<b>k</b> parameter sets the target level of black + (K) when creating a B2A CMYK output tables. This is often called a + black level, a black inking rule, black generation, or under color + removal. These set the target black level:<br> + <br> + <b> -kz</b> selects minimum black (0.0)<br> + <b> -kh</b> selects a black level value of 0.5<br> + <b> -kx</b> selects the maximum possible black (1.0)<br> + <b> -kr</b> selects a linear level ramp, starting at minimum black + for highlight, and maximum black for shadow (equivalent to -kp 0 0 1 + 1 1). This is the default.<br> + <b>-kt</b>, will preserve the black amount from the source (CMYK) + profile to the destination (CMYK) profile as much as possible. + This may be most useful in creating a CMYK to CMYK conversion + between two different press conditions, while preserving as much as + possible the black only use for text etc. in anything + converted. Note that if the source black point is darker than the + destination, composite black will still be generated for K only + input. The <span style="font-weight: bold;">-fk</span> option can + be used to avoid this behavior.<br> + <b>-ke</b>, will preserve the black amount from the destination + profile B2A table (CMYK).<br> + <br> + <b><a name="kp"></a>-k p stle stpo enpo enle shape</b> allows + an arbitrary black locus ramp to be defined, consisting of a + starting value (stle) for highlights, a breakpoint L value (stpo) + where it starts to transition to the shadow level, an end breakpoint + L (enpo) where it flattens out again, and the finishing black level + (enle) for the shadows. There is also a curve parameter, that + modifies the transition from stle to enle to either be concave + (ie. the transition starts gradually and and finished more + abruptly) using values 0.0-1.0, with 0.0 being most concave, or + convex (the transition starts more abruptly but finishes gradually), + using values 1.0-2.0, with 2.0 being the most convex.<br> + <br> + Typical black value generation curve with parameters something like: + -kp 0 .1 .9 1 .5<br> + <br> + <tt> 1.0 K | + enpo<br> + +| + + + + _______ enle<br> + +| + + + + /<br> + +| + + + + /<br> + +| + + + + /<br> + +| + + + + /<br> + + stle | ------/<br> + + +-------------------<br> + 0.0 K + 0.0 + stpo 1.0<br> + +White + + + Black<br> + <br> + </tt>For minimum sensitivity of printed output to the lighting + spectrum, it currently seems best to use the maximum possible black, + but other black generation levels (ie. 0.3 to 0.5) may well be + preferred if one wants to minimize the noisy appearance of black on + an inkjet device, or if the banding behaviour or other rendering + flaws of the printer is to be minimized. <br> + <br> + Note that the black level curve is applied throughout the gamut, + resulting in GCR (Grey Component Replacement). There is no facility + to restrict black to just neutral colors, hence UCR is not currently + supported.<br> + <br> + <b><a name="kq"></a>-k q stle0 stpo0 enpo0 enle0 shape0 stle2 stpo2 + enpo2 enle2 shape2</b> is a combination of the <b>-kt</b> and <b>-kp</b> + functionality, with the black being preserved in CMYK to CMYK + linking, with the output black constrained to be between the first + and second set of curve parameters.<br> + <br> + The <a href="xicclu.html">xicclu</a> tool can be used to plot out + the resulting black level for a given set of parameters, by using + the <a href="xicclu.html#g">-g</a> flag of a profile already + created from the same .ti3 file.<br> + <br> + <a name="K"></a> <span style="font-weight: bold;">-K parameters.</span> + Any of the <span style="font-weight: bold;">-k</span> options above + can use the <span style="font-weight: bold;">-K</span> version, in + which rather than a black value target being defined by the inking + rule, a black <span style="text-decoration: underline;">locus</span> + target is defined. For each lookup, the minimum possible black level + and the maximum possible black level is determined, the former + corresponding to a locus target value of 0, and the latter + corresponding to a locus target value of 1. For instance, at the + white point, no black will be used in the output, even if the black + locus specifies a maximum (since the maximum amount of black that + can be used to print white is actually zero). Similarly, at the + black point, black may well be used, even if the black locus + specifies zero black (since a certain amount of black is needed to + achieve the desired density of color). <br> + <tt> </tt><br> + <a name="l"></a> The <b>-l</b> <i>tlimit</i> parameter sets the + total ink limit (TAC, Total Area Coverage) for the CMYK separation, + as a total percentage from 0% to 400%. This affects the gamut + assumed for the destination profile, as well as the ink limit in the + generated device link. The limit value should generally be set a + little below the value used in the test chart generation, to avoid + the very edges of the gamut. If the test chart ink limit has been + chosen to be a little beyond an acceptable level, then this number + should be the acceptable level. Although limits can be set below + 200%, this will generally restrict the color gamut noticeably, as + fully saturated secondary colors will not be reproduced. Values are + between 220% and 300% for typical printing devices. By default, a + total ink limit will be estimated from the destination profile B2A + table. The ink limit will be in final calibrated device values if + the profile includes calibration information.<br> + <br> + <a name="L"></a> The <b>-L</b> <i>klimit</i> parameter sets the + black channel ink limit for the CMYK separation, as a total + percentage from 0% to 100%. This affects the gamut assumed for the + source profile, as well as the ink limit in the generated device + link. For printing press like devices, this can be used to prevent + the black channel screening pattern "filling in". Typical values + might be from 95% to 99%. By default, a black ink limit will be + estimated from the source profile B2A table. The ink limit will be + in final calibrated device values if the profile includes + calibration information.<br> + <br> + <b><a name="P"></a></b>The <b>-P</b> option causes a diagnostic 3D + <a href="File_Formats.html#VRML">VRML</a> plots to be created that + illustrate the gamut mapping generated.<br> + <br> + <a name="p1"></a>The <i><b>inprofile</b></i> argument specifies the + source profile. This is the color space/device we are attempting to + emulate in the overall conversion. A <small>TIFF or JPEG file with + embedded profile may be used here.</small><br> + <br> + <a name="p2"></a>The<i><b> outprofile</b></i> argument specifies the + destination profile. This is the device we are actually displaying + on or printing to. A <small>TIFF or JPEG file with embedded profile + may be used here.</small><br> + <br> + <a name="p3"></a>The <i><b>linkedprofile</b></i> argument specifies + the resulting device link profile. This profile will contain the + color transform from the source space to destination space.<br> + <br> + For information on typical usage, see the <a href="Scenarios.html">Typical + + + Usage Scenarios</a> page.<br> + <br> + <br> + <br> + <br> + <br> + <br> + <br> + <br> + <br> + <br> + </body> +</html> |